Flat UI is an amazing free Bootstrap theme from Designmodo available on GitHub. With Flat UI theme, most of the bootstrap elements have been customized to look simple and flat. Few of the elements needs additional JS plugins, which takes a bit effort to implement – if you wish to use it in your project.

You can go through the getting started guide here to get up and running without major glitches. If you wish to download the PSD of the theme, you can be happy. It is available for download.

A Pro version of the same theme with more elements and features are available for purchase as well.